Objective: Regulating the impedance of our joints is essential for the effective control of posture and movement. The impedance of a joint is governed mainly by the mechanical properties of the muscle-tendon units spanning it. Many studies have quantified the net impedance of joints but not the specific contributions from the muscles and tendons. The inability to quantify both muscle and tendon impedance limits the ability to determine the causes underlying altered movement control associated with aging, neuromuscular injury, and other conditions that have different effects on muscle and tendon properties. Therefore, we developed a technique to quantify joint, muscle, and tendon impedance simultaneously and evaluated this technique at the human ankle. Methods: We used a single degree of freedom actuator to deliver pseudorandom rotations to the ankle while measuring the corresponding torques. We simultaneously measured the displacement of the medial gastrocnemius muscletendon junction with B-mode ultrasound. From these experimental measurements, we were able to estimate ankle, muscle, and tendon impedance using non-parametric system identification. Results: We validated our estimates by comparing them to previously reported muscle and tendon stiffness, the position-dependent component of impedance, to demonstrate that our technique generates reliable estimates of these properties. Conclusion: Our approach can be used to clarify the respective contributions from the muscle and tendon to the net mechanics of a joint. Significance: This is a critical step forward in the ultimate goal of understanding how muscles and tendons govern ankle impedance during posture and movement.

Background As the COVID-19 pandemic moves into the survivorship phase, questions regarding long-term lung damage remain unanswered. Previous histopathological studies are limited to autopsy reports. We studied lung specimens from COVID-19 survivors who underwent elective lung resections to determine whether post-acute histopathological changes are present. Methods In this multicenter observational study, we included adult COVID-19 survivors (n=11) who had recovered but subsequently underwent unrelated elective lung resection for indeterminate lung nodules or lung cancer. We compared these to an age- and procedure-matched control group who never contracted COVID-19 (n=5), and an end-stage COVID-19 group (n=3). A blinded pulmonary pathologist examined the lung parenchyma focusing on four compartments: airways, alveoli, interstitium, and vasculature. Results Eleven COVID-19 survivors with asymptomatic (n=4), moderate (n=4), and severe (n=3) COVID-19 infections underwent elective lung resection at a median 68.5 days (range 24-142) after COVID-19 diagnosis. The most common operation was lobectomy (75%). On histopathological examination, no differences were identified between the lung parenchyma of COVID-19 survivors and controls across all compartments examined. Conversely, patients in the end-stage COVID-19 group showed fibrotic diffuse alveolar damage with intra-alveolar macrophages, organizing pneumonia, and focal interstitial emphysema. Conclusions In this first study to examine the lung parenchyma of COVID-19 survivors, we did not find distinct post-acute histopathological changes to suggest permanent pulmonary damage. These results are reassuring for COVID-19 survivors who recover and become asymptomatic.

Objective To compare outcomes of juvenile nasopharyngeal angiofibroma (JNA) resection between embolized and non‐embolized cohorts, and between transarterial embolization (TAE) and direct puncture embolization (DPE). Data Sources Per PRISMA guidelines, PubMed, Embase, Web of Science, Scopus, and Cochrane databases were searched for publications prior to or in 2021. Materials and Methods Original English manuscripts investigating the resection of JNA with and without preoperative embolization were included. Embolization type, recurrence rate, complication rates, blood loss, and transfusions were extracted. Risk of bias was assessed by the Risk of Bias in Non‐randomized Studies—of Interventions method. Results There were 61 studies with 917 patients included. Preoperative embolization was performed in 79.3% of patients. Of those embolized, 75.8% (N = 551) underwent TAE and 15.8% (N = 115) underwent DPE. JNA recurrence in embolized patients was lower than in non‐embolized patients (9.3% vs. 14.4%; odds ratio [OR]: 0.61, 95% confidence interval [CI]: 0.35, 1.06). DPE resulted in lower rates of disease recurrence (0% vs. 9.5%; OR: 0.066, 95% CI: 0.016, 0.272) and complications (1.8% vs. 21.9%; OR: 0.07, 95% CI: 0.02, 0.3) than TAE. A random effects Bayesian model was performed to analyze the difference in mean blood loss in 6 studies that included both embolized and non‐embolized patients. This analysis showed a mean reduction in blood loss of 798 mL in the embolized group. Conclusions We found embolization decreases blood loss in JNA resection. DPE led to improved recurrence and complication rates when compared to TAE, but future prospective studies are needed to further evaluate which embolization technique can optimize outcomes in JNA. Level of Evidence NA Laryngoscope, 133:1529–1539, 2023

Objectives Insurance coverage plays a critical role in head and neck cancer care. This retrospective study examines how insurance coverage affects nasopharyngeal carcinoma (NPC) survival in the United States using the Surveillance, Epidemiology, and End Results (SEER) program database. Design, Setting, and Participants A total of 2,278 patients aged 20 to 64 years according to the International Classification of Diseases for Oncology (ICD-O) codes C11.0–C11.9 and ICD-O histology codes 8070–8078 and 8080–8083 between 2007 and 2016 were included and grouped into privately insured, Medicaid, and uninsured groups. Log-rank test and multivariable Cox's proportional hazard model were performed. Main Outcome Measures Tumor stage, age, sex, race, marital status, disease stage, year of diagnosis, median household county income, and disease-specific survival outcomes including cause of death were analyzed. Results Across all tumor stages, privately insured patients had a 59.0% lower mortality risk than uninsured patients (hazard ratio [HR]: 0.410, 95% confidence interval [CI]: [0.320, 0.526], p < 0.01). Medicaid patients were also estimated to have 19.0% lower mortality than uninsured patients (HR: 0.810, 95% CI: [0.626, 1.048], p = 0.108). Privately insured patients with regional and distant NPC had significantly better survival outcomes compared with uninsured individuals. Localized tumors did not show any association between survival and type of insurance coverage. Conclusion Privately insured individuals had significantly better survival outcomes than uninsured or Medicaid patients, a trend that was preserved after accounting for tumor grade, demographic and clinicopathologic factors. These results underscore the difference in survival outcomes when comparing privately insured to Medicaid/uninsured populations and warrant further investigation in efforts for health care reform.

Objective: Regulating the impedance of our joints is essential for the effective control of posture and movement. The impedance of a joint is governed mainly by the mechanical properties of the muscle-tendon units spanning it. Many studies have quantified the net impedance of joints but not the specific contributions from the muscles and tendons. The inability to quantify both muscle and tendon impedance limits the ability to determine the causes underlying altered movement control associated with aging, neuromuscular injury, and other conditions that have different effects on muscle and tendon properties. Therefore, we developed a technique to quantify joint, muscle, and tendon impedance simultaneously and evaluated this technique at the human ankle. Methods: We used a single degree of freedom actuator to deliver pseudorandom rotations to the ankle while measuring the corresponding torques. We simultaneously measured the displacement of the medial gastrocnemius muscle-tendon junction with B-mode ultrasound. From these experimental measurements, we were able to estimate ankle, muscle, and tendon impedance using non-parametric system identification. Results: We validated our estimates by comparing them to previously reported muscle and tendon stiffness, the position-dependent component of impedance, to demonstrate that our technique generates reliable estimates of these properties. Conclusion: Our approach can be used to clarify the respective contributions from the muscle and tendon to the net mechanics of a joint. Significance: This is a critical step forward in the ultimate goal of understanding how muscles and tendons govern ankle impedance during posture and movement.